Heater



Get. 16, 1945. F. o. HESS ETAL 2387 022 HEATER Filed Sept. 5, 1941 i 1 E AC l E K D Patented a. 16, 1945 HEATER Frederic 0. Hess, Germantown, and Richard E. B.

Wakefield, Aidan, Pa., assignors to Selas'Cora corporation of Pennporation of America sylvania Application September 5, 1941, Serial No. 409,613

' roam, (c1; 126-"105) The general object of the present invention is to provide improved heating and distributing means adapted, for example to supply heated air for use in heating the cabin and other spaces of transport and war planes which are desirably heated and for supplying heated air for defrosting and other special purposes.

A specific object of the present invention is to provide an improvement for delivering heated air through a plurality of outlets and in some cases at a pressure appreciably above the pressure panying drawing and descriptive matter in which we have illustrated and described preferred embodiments of the invention.

Of the drawing:

Fig. 1 is an elevation, partly broken away and in section, of an air heater constructed in accordance with the present invention; and

Fig. 2 is a plan view of the heater shown in Fig. 1.

The air heater shown in Figs. 1 and 2 comprises a casing AC generally circular in transverse section and having an air inlet at the bottom and an air outlet at the top of the casing.

Within the casing AC is provided air heating means comprising a burner body B formed with an annular slot-like burner inlet chamber B provided at its top with an orifice wall C of ceramic material, preferably in the form of radial laminae, with grooves in their sides which serve as burner orifices. A combustible mixture of air and atomized gasoline is supplied to the chamber B and passes therefrom through the orifices in the wall C into the heating chamber D in which it is burned. The heating chamber D as shown is annular in horizontal cross section and has side walls formed of sheet metal parts E including fin or rib portions E extending into the heating chamber and other fin or rib parts'E which are external to the heating chamber and extend away from the latter into air heating spaces F and f at the outer and inner sides, respectively, from the heating chamber and separated from the latter by the walls E.

The air heated by the heater is moved from the space in which the heater is mounted through the spaces F and ,f by a fan or rotary blower GB,

which, as shown in Fig. 1, is driven by an electric motor H carried by the body B through arms H.

A combustible mixture of air and atomized gasoline is supplied to the burner inlet chamber B by means of the general character disclosed in application, Serial No. 365,804, now Patent No. 2,314,089, granted March 16, 1943, and comprising a high speed fan J of the turbo blower type driven by an electric motor K. The latter is shown herein as below the motor H and within the space or central cavity formed by the heating chamber. The outlet J' of the fan J opens to the burner inlet chamber B and the fan draws air, ordinarily from the external atmosphere, through an inlet pipe J Gasoline is supplied under pressure through a pipe L from a suitable source of supply, and is discharged from the pipe L through a fine orifice L in the form of ajet of relatively small cross section into the path of movement of the impeller blades of the fan J. The gasoline thus subjected to the beater action of the rapidly moving impeller blades, is atomized, and the fan J thus forms a means for supplying a combustible mixture of combustible air and atomized gasoline to the chamber B. Any atomized or condensed gasoline, which may drip or run down in the inlet J in starting the apparatus up from a cold condition, is absorbed by porous ceramic material U and is vaporized out of the latter when the apparatus heats up, as is disclosed and claimed in our prior application, Serial No. 378,916, filed February 14, 1941. As shown, the motor K is directly supportedby the burner body B.

Products of heating formed in the .combustion chamber D are discharged into the external atmosphere through means comprising an outlet pipe 0' leading laterally away from the upper end of the chamber D through the wall of the casing AC.

A motor driven fan (not shown) may be mounted on the side of casing AC, if desired, for exhausting the products of combustion through conduit 0', in a manner well known in the art.

The general operation of the apparatus shown in Figs. 1 and 2 will be readily understood by those skilled in the art. By the use of a recirculating fan GB of suitable type the pressure of the air recirculated may be readily increased as much as is necessary to insure the proper volume of air flow through the spaces F and f and to provide the pressure head needed for the movement of air through distribution piping to points and devices such as defrosters located at some distance from the heater.

In accordance with our invention the recirculating ran GB is mounted in a housing T carried by the casing AC of the heater. The inlet T of the fan housing T receives all of the heated air moved through the heater air spaces F and f, and said housing is provided with a plurality of separate outlets T to each of which a corresponding discharge conduit T is connected. The conduits number of hot air outlets as in the heater illustrated and just described, permits the heater unit, of suitable light weight and bulk to provide a plurality of separate and separately usable heating eilects without requiring the heater to be objectionably large, or heavy and while avoiding the structural and operating complications inherent T or some of them, may well 'be in the form of 1 flexible hose sections and each of them is adapted to convey a portion of the air heated by the heater to a windshield defroster or other device or pertlon of the airplane desirably receiving, at times at least, a fractional part of the air heated. The fans GB and J are driven by separate motors H and K located axially in the space surrounded by the heating chamber D or the heater and subject to the direct cooling action of some of the air moved through and heated in the heater.

It will now be understood that the heating unit forming the chamber D provides a relatively extensive heat transfer Surface disposed within the casing AC. The heating unit forms a central cavity within which is disposed the motor H whose shaft M projects into the housing T to which the fan GB is fixed. The housing T serves as an end plate for the casing AC and the spaced apart walls thereof are at right angles to theaxis of the casing. The inlet T of the ian chamber is sufliciently large so that the housing T may be secured in position and carriedat the upper end of the casing AC after the fan GB is fixed to the shaft M.

Special features of the finned heat exchanger portion of the heater disclosed but notclaimed herein,"are claimed in the copending application, Serial No. 409,440, filed concurrently with the instant application by the said Frederic O. Hess.

In the iormillustrated our improved heater is characterized by its mechanical simplicity and small weight and bulk relative to its air heating capacity. Our improved heater was devised and is adapted for use in an airplane in which a plurality of separate heating effects for different spaces or defrosting and other devices are needed. For example, in one particular war plane use contemplated in designing the heater shown, two 01' the conduits T lead to two separate pilot window defrosting devices, another conduit T leads to a bomb sight heating means, a fourth conduit 1' supplies air for heating a galley, and the two remaining conduits 'I are employed to separately supply heating air to two gun turrets.

The provision of a heater having a moderate in the use of a separate heater to produce each of the difierent heating efiects, and with some economy in space and weight.

While in accordance with the provisions of the statutes, we have illustrated and described the best form oi embodiment of our invention now known to us, it will be apparent to those skilled in the art that changes may be made in the form 01' the apparatus disclosed without departing from the spirit of our invention, as set forth in the following claim.

Having now described our invention, what we claim as new and desire to secure by Letters Patent is:

An independently operable heater of the internal combustion type comprising an annular casing defining a space having openings at the ends thereof, a heating unit having a relatively extensive heat transfer surface disposed within the space and formed to provide a central cavity therein, means to eflect combustion of a fuel adaptedto be supplied to the heater to cause heating of the heating unit, the heating unit being capable of heating air adapted to flow into the casing through an opening at an end thereof, a housing secured to the opposite end of the casin and serving as an end plat therefor, said housing having spaced apart walls at right angles to the axis of the casing, the wall of the housing nearer to the casing having an inlet therein, a fan within the housing between the walls thereof adapted to cause said flow of air into the casing past the heating unit and draw such heated air into the housing through the inlet, the housing having a number of spaced apart outlets for discharging heated air therefrom at a plurality of places, an electric motor mounted within the casing and positioned in the cavity therein, said motor having a shaft projecting into the housing at right angles to the walls thereof, said fan being fixed to the shaft, and the inlet being sufilciently'large that the housing may be secured in position at the end of the casing after the fan is fixed to the shaft.

FREDERIC O. HESS. RICHARD E. B. WAKEFIELD. 

